Global Economy — 2026-07-04

SIPRI Warns US-Iran Deal Could Let Iran Restrict Strait of Hormuz Navigation Permanently, Setting Global Precedent

BLUFFormal Iranian tolls or passage restrictions on Hormuz shipping are unlikely by mid-September, but the memorandum's ambiguous post-60-day language grants Tehran a durable legal pretext for future unilateral control.

A SIPRI commentary published on 2 July, relayed by Sri Lanka Guardian 12, warns that the US-Iran Islamabad Memorandum signed on 17 June contains language that could restrict navigation through the Strait of Hormuz. The memorandum commits Iran to guaranteeing safe passage of commercial vessels for 60 days after signing, after which the text leaves open new arrangements governing maritime services and navigation through the strait 12. SIPRI's analysis states this wording could permit Iran to impose charges or tolls on transiting vessels once the 60-day window lapses 12. The memorandum also calls for dialogue among Iran, Oman, and other regional coastal states to define future administration of the strait; SIPRI notes that Iranian and Omani domestic law has previously required prior authorization for certain military vessels 12. SIPRI warns the concession could embolden China to assert similar restrictions in the South China Sea and Russia along the Arctic's Northern Sea Route, and that military pressure can reshape international maritime norms 12.

Analysis
Iran is unlikely to impose formal tolls or authorization requirements on Hormuz shipping within 30 days of the memorandum's 60-day passage guarantee lapsing, by September 15. Moderate confidence reflects a single analytical source and the absence of any observable Iranian or Omani administrative steps toward implementation. Tehran's incentive runs toward preserving the fragile truce and avoiding a confrontation with US and European naval assets that have historically contested passage restrictions. The memorandum's ambiguity is more likely to surface first in diplomatic dialogue among Iran, Oman, and regional states than in unilateral Iranian enforcement action. Tehran's rejection of French-Omani mine-clearance assistance and the concurrent Middle Corridor traffic surge indicate Iran positioning for unilateral Hormuz stewardship rather than multilateral governance.

2 sources

The United States deal with Iran could put freedom of navigation at risk worldwide - SIPRI
US–Iran Deal Raises Fears Over Global Freedom of Navigation - Sri Lanka Guardian